Comparing Fission-product Yields from Photon-induced Fission of <sup>240</sup>Pu and Neutron-induced Fission of <sup>239</sup>Pu as a Function of Incident Energy

ORAL

Abstract

The Bohr Hypothesis, one of the most fundamental assumptions in nuclear fission theory, states that the decay of a compound nucleus with a given excitation energy, spin and parity is independent of its formation. Using fission product yields (FPYs) as a sensitive probe, we have performed novel high-precision test of the combined effects of the entrance channel, spin and parity on the fission process. Two different reactions were used in a self-consistent manner to produce a compound 240Pu nucleus with the same excitation energy: neutron induced fission of 239Pu and photon-induced fission of 240Pu. The FPYs from these two reactions were measured using quasimonoenergetic neutron beams from the TUNL’s FN tandem Van de Graaff accelerator [1] and quasimonenergetic photon beams from the HIGS facility. An updated comparison of the FPYs from 239Pu(n,f) at En=1.5 and 4.6 MeV with those from 240Pu(γ,f) at Eγ=8 and 11.2 MeV will be presented.



[1] M.E. Gooden et al., “Energy Dependence of Fission Product Yields from 235U, 238U and 239Pu for Incident Neutron Energies Between 0.5 and 14.8 MeV.” Nuclear Data Sheets 131, 319 (2016).

*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

Presenters

  • Jack A Silano

    • Lawrence Livermore National Laboratory

Authors

  • Jack A Silano

    • Lawrence Livermore National Laboratory
  • Anthony Paul D Ramirez

    • Lawrence Livermore National Laboratory
    • LLNL
  • Ronald C Malone

    • Lawrence Livermore National Laboratory
  • Anton P Tonchev

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab
  • Mark A Stoyer

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab
  • Roger Henderson

    • Lawrence Livermore Natl Lab
  • Nicolas Schunck

    • Lawrence Livermore Natl Lab
  • Werner Tornow

    • Duke University
    • Duke University & Triangle Universities Nuclear Laboratory
  • Calvin R Howell

    • Duke University
    • Duke University & Triangle Universities Nuclear Laboratory
  • FNU Krishichayan

    • Duke University
    • Duke University, Triangle Universities Nuclear Laboratory
  • Sean W Finch

    • Duke University
  • Matthew E Gooden

    • LANL
    • Los Alamos National Laboratory